1. Field of the Invention
Embodiments of the invention generally relate to optical fibers that are suitable for use in sensing applications exposed to radiation environments.
2. Description of the Related Art
Interferometer and grating based optical sensors rely on light transmission through single mode optical fibers. A fiber optic gyroscope (FOG) exemplifies one type of sensor in which light is guided through a sensing coil of fiber and then detected to determine angular rotation of the FOG based on modulation of the light detected. However, packaging and deployment of optical sensors frequently subjects the fiber to bending that can detrimentally affect both optical and mechanical properties of the fiber. Furthermore, the fibers may include glass index-modifying dopants such as germanium and phosphorus that sensitize the glass leading to high attenuation or even total darkening when operating in harsh environments that expose the fiber to nuclear radiation and hydrogen. Sensing applications in such harsh environments utilizing any prior available fiber suffer from one or both of these problems associated with the fiber.
Therefore there exists a need for optical fibers with improved performance characteristics, such as resistance to bend-induced attenuation and radiation-induced attenuation, and methods of manufacturing these optical fibers.